The quality of milk determines its technological usefulness, especially in cheese production. The presence of undesirable microorganisms in milk results in a decrease in its quality and destruction of the micellar structure of casein proteins. Unfavorable changes occurring in milk concern primarily the protein, therefore there is a need to protect these milk components. The aim of the presented experiment was to clarify the influence on the hygienic quality and technological suitability of raw milk, with the addition of Lactobacillus rhamnosus (LR). The use of protective additives in the form of lactic acid bacteria (LR) strains allows for support the protection of milk proteins. In the conducted experiment, the effect of the addition of LR on the hygienic quality and cheese-making usefulness of raw milk was examined. The changes occurring in the milk, were determined by analyses performed in taken after: 1, 5, 15, 25, 38 and 48 hours after milking. In milk with the addition of LR, lower total bacteria count (TBC) variability and higher lactose content were noted, and a significant negative correlation between lactose content and TBC was found. The amount of κ-casein in milk with LR was on average 0.006 mg mL^-1 higher than in control milk (p <0.05), and the correlation with TBC was negative (p <0.05). The experiment also showed that the κ- content began to decrease after the 5^th hour of storage, but in the case of milk without bacterial protection, this process was more dynamic (on average 0.003 mg mL^-1 less). The study confirms that the addition of LR can effectively improve the quality of milk and its suitability for cheesemaking.